Heat pump operated system for house heating



Feb. 5, v1957 w. GAY 2,780,415

HEAT PUMP OPERATED SYSTEM FOR HOUSE-HEATING Filed Feb. 23, 1952 `7 sheets-sheet 1 Feb. 5, 1957 F. w. GAY

HEAT PUMP OPEEATED SYSTEM FOR' HOUSE HEATING Filed Feb. 2:5. 1952 7 Sheets-Sheet 2 Feb. v5, 1957 F. w. GAY

HEAT PUMP OPERATED SYSTM FOR HOUSE HEATING Filed'Feb. 2s, 1952 7 Sheets-Shogi 3 l fum@ Feb. 5', 1957 Filed Feb. 2s. 1952 F. w. GAY 2,780,415 HEAT PUMP OPEEATED SYSTEM FOR HOUSE HEATING 7 Sheets-Sheet 4 Feb. 5, 1957 F W, GAY

HEAT PUMP OPERATED SYSTEM FOR HOUSE HEATING '7 Sheets-Sheet 5 i Filed Feb. 23, 1952 INVENTOR.

Feb. 5, 1957 E F. w. GAY

HEAT PUMP OPERATED SYSTEM FOR HousE HEATING Filed Feb. 23, 1952 l 7 Sheets-Sheet 6 E W e A KAN. DZWND Feb. 5,- 1957 F. w. GAY 2,730,415 HEAT PUMP OPERATED SYSTEM FOR HOUSE HEATING Filed Feb. 23, 1952 '7 Sheets-Sheet 7 Q O Q sa f a E L h 4o U L 5 60 j '-1 s 5 m 4 I0 20 o 40 50 60 70 mao 2000 3000 4000 5000 ouooon TEMPERATURE F" WK3 P YER TL :o so y zu 3 30g 40 20A` Y u S S" 5q mE 5 u C 5g o o 500 w00 i500 8000 3500 3000 5590 4000 00 5000 fiouks u YEIAR aufm-30p sr 4s: sor, nemers l l 1 1 l l s 2.11.1005- 55 4 s coP INVENTOR. jr'a'ef/Z 3 said heat pump will be high and the electrical energy consumption will be low.

It is a further object of this invention to partially bury a house in the earth and provide means to use solar energy to raise the temperature of the surrounding earth whereby the living spaces adjacent said warm earth are kept in a dry and livable condition.

Other objects of this invention, not at this time more particularly enumerated, will be understood from the following detailed description.

Illustrative embodiments of this invention are shown in the accompanying drawings, in which:

Fig. 1 is a schematic cross-sectional elevation of a house adapted to be heated by a heat pump operated heating system according to this invention, this view showing locations of the heat pump, attic heat exchanger, house heat dispensing heat exchanger, and earth heat storage area, the latter being located beneath the house, and Fig. 1A is a fragmentary view, showing the earth heat storage area located exteriorly of the house.

Fig. 2 is a schematic view of one embodiment of a heat pump operated house heating system according to this invention such as shown in Fig. 1.

Fig. 3 is a schematic view of modified embodiment of a heat pump operated house heating system according to this invention; and Fig. 4 is a schematic view of another modified embodiment of a heat pump operated house heating system according to this invention.

Fig. S is a detail vertical sectional view of an attic heat recovery apparatus, taken on line 5--5 in Fig. 1, but drawn on an enlarged scale; Fig. 6 is a vertical sectional view of the same, taken in line 6-6 in Fig. 5; and Fig. 7 is a vertical sectional view of the same, taken on line 7-7 in Fig. 6.

Fig. 8 is a fragmentary vertical sectional view through an earth heat storage area of the system, showing the heat transfer fluid conducting coils therein provided with one way heat conductor connected therewith and leading thereto from deep earth beneath said storage area; Fig. 9 is a vertical longitudinal section, taken on line 9--9 in Fig. 8, but drawn on an enlarged scale; and Fig. 10 is a detail transverse sectional view, taken on line 10-10 in Fig. 9.

Fig. 1l is a graph illustrating the adaptation of a heat pump to a house heating system according to this invention; Fig. l2 is a graph indicating duration curves in hours per year at various temperatures in a temperate area, such e. g. as the New York metropolitan district, from which curves heating requirements can be ascertained; and Fig. 13 is a graph showing a curve indicating power requirement when the heat pump receives heat from the earth heat storage area when outdoor temperature is very low, i. e. approximately at zero F.

Similar characters of reference are employed in the hereinabove described views, to indicate corresponding parts.

Referring first to Fig. 1 which illustrates a house structurehaving an attic space above its living rooms. The house roof 151, which extends over the attic space, is constructed of heat conductive material, preferably comprising aluminum painted black, although it may comprilse thin wood shingles or other heat conductive mate na insulating but radiant heat conducting material 152, such as glass, corrugated transparent plastic material or the like. The end gables of the house are preferably heat insulated, 4and louvers are provided in the attic walls, whereby to be adapted to stand open in the summer, but to be closed in the winter. A heat pump or compressor 3, preferably located `in the lower region of the house, pumps heat from an evaporator 1 to a condenser 5 in the usual manner. As shown more in detail in Fig. 2, a pump 17P pumps a cold heat transfer fluid from an evaporator coil 10 to an attic heat recovery apparatus 107 in warm winter weather.V This cold heat transfer fluid -is warmed Said roof 151 is covered with a convective heatl by attic air as it passes through the attic heat.recovery apparatus 107, and carries the heat so received to said evaporator coil 10. The warmed heat transfer fluid gives up its received heat to the liquid refrigerant in the evaporator 1, causing said refrigerant to boil. In very cold winter weather pump 17P is shut down and pump 20P is operated. The cold heat transfer uid is thereupon pumped through the conducting coils 22, which are buried in the heat storage area 23 beneath the house, and back to the evaporator coil 10, thus transferring heat from the earth heat storage area to the liquid refrigerant in evaporator 1, causing said refrigerant to boil. When pump 26P is operated, it pumps hot heat transfer uid from the coil 12 in condenser 5 to a house heat dispensing heat exchanger 106, from which heat is emitted to warm the house air, whereupon the somewhat cooled heat transfer fluid passes back to the condenser coil 12 and is again warmed as it condenses the hot compressed refrigerant gas delivered to the condenser by the compressor 3. When the demand for house heat is satisfied, pump 26P is stopped, and pump 30P is put in operation. Said pump 30P operates to circulate the hot heat transfer uid through the coils 22 in thc earth heat storage area 23 and back to the coil 12 in condenser 5, so that heat delivered to the condenser 5 by operation of compressor 3 is conducted to and stored in the earth heat storage area 23.

The attic heat recovery apparatus 107 can be arranged to receive attic air regardless of its location, i. e. although it is preferable to locate said attic heat recovery apparatus within the attic, this is not essential so long as its intake communicates with the attic air. It has been found that in sunny winter weather the attic air will receive enough heat to remain warm enough to efficiently serve the heat recovery device 107 for delivery of a full quota of heat to the heat pump notwithstanding the outdoor air may bc at freezing temperature.

As shown in Fig. 1, above the earth heat storage area 23 and its contained heat transfer fluid conducting coils 22, there shown beneath the house, it is desirable to provide a series of trenches T which are traversed by a perforate water pipe P imbedded in coarse gravel G with which said trenches are filled, so that water in desired quantity may flood these trenches when needed. A battery B is connected between this water pipe P and the earth heat storage area coils 22 so as to cause Water to flow from the former to the latter. When the earth is found to have low thermal conductivity, water is caused to ow to the coils 22 by electric osmosis, thus tending to hold moisture around said coils for a long period.

As shown in Fig. 1A, the earth heat storage area 23 and its contained heat transfer fluid conducting coils 22 can optionally be located exteriorly of but adjacent to the house. In such case the area should be walled in by walls W to prevent entrance into said area of cold moisture which may saturate the outer earth after a storm. Said walls prevent both inward and outward migration of moisture to and from the earth heat storage area, and thus prevents dissipation of stored heat by carrying away thereof by migrating moisture. The means above described for holding moisture by electric osmosis around the coils 22 may be used with the exterior earth heat storage area, if desired.

Referring now to Fig. 2 in which one embodiment of the' system is schematically shown in detail, cold liquid refrigerant gas is delivered by conduit 2 from the evaporator 1 to the compressor 3, which is driven by electric motor 14, and is compressed and heated by operation of the compressor. The hot refrigerant is delivered by con duit 4 from the compressor 3 to the condenser 5, and is condensed in the latter so as to fill the same to a level 13. The condensed liquid refrigerant is discharged from the condenser 5 through pipe 6 for ow through coils 7, and thence, by way of return pipe 8, through a oat valve 9 back to evaporator 1, whereby to flood the inand raGlEQSS; theaheatgtran on Theranrangernent fbeinsf suehffhataldis f.; through the hot upper levels of said earth he area;randalastlyathtgugh.the @01er ilowereleveleif 'the' latter; lthattherefrigerantfeives't upfsit sfartedf-,f.Thefcirulatonz- 0f .hat heatfftrmsferf tofthe 4th a'r011.nd=.thecoils 7 and@ The.evaporatorY llid21392611231@hfhlheatingftifil06fbeingtOPPsdfn coil 10;,carries: heat -transferfrluid- Thefliquih refrigerant: fau .10l.isalsgstopped KByEvits operation, p urnpi lSOR; i111:evaporatorf 1, by boilingt-extractsheabfrom the heat 10y HOWrdfawS. hotfhfffrallser; llidzfmm ndndl: transferftluidowingtingsaidevaporatorcoil, thus cooling, l2 through Pipe 25 md Check Valve 30C, and forcestherV Satama@ transfer mida-Heat transfea huid `hows in the.: hor tudfthrfyghgpipel@divine-22H39 ,the earth haar condenser .coi1f-12:': The rhot compres s,ed,-.refrigerantgas, Storage geile; 22;;0f5theiearth yheat..storageareas;23..g In. discharged-:fromatheg compressor; through 'pipe into". owfngrtlllplglgh saidcoils 2.2,);thehotgheatvtransfergilui@ condenserr5is;condensed.,:by;.the heat-.ftransferfuidfowe 15- fszfgiivesfu @larg ingathroughr saidicondenserscoil 12', so` that -thetemperarV Gfzthezffaflh heltofgs. ri ture-'ofosaid heat transfer iluichis'raised.L ll'lldlillshlllg@mOplqlLnd Consider-vnows the,l heat '-soures which sserverthe.heatA with@ Uw..ef .Vel pumps.v Inxaveragewinterweather:.( above. approximatehz` 252'? F2)V relatively cold. heattransferauid WilLbe-drawnJ through rpipe 16: andlicheclc valvex17C by1'pump 17Effrom; ther evaporator \coi1:f10 Pump :17P1f'willxforce this rela-r tively coldheat transfer'- fuidv Ythrough 1.p1pe18ito'.the: attic. heatl-recovery-device 107,' detailedwdescrition: of which willgib'e= hereirilater setforth.f` Theheatitransfer vfluid* o is passingthrough the atticL heat exchangerrilflE extracts heat from rel-ativelyfwarmfir blownthrough said heat` exchanger *'10V7E1 vbyva fang107F-fwhiehfis ldriven by` a ruotorjf107Mv The-cold t'lheautf transfer-1' uid'lisy thus n VICSQS- warmed and ows yorrfthrough-pipe19ifa11dpipe 15b/acl;l 001 Sll-..-..ggl;g;107 to Kand through the evaporatoricoil'l; and= the=-heatre Wltrhzi-h@ fllllgf, 1. r ceivedtherebyin th'e heat:exchanger?107E3isfextractei anti 10113135 ,A111 from the coil IObyLthe' colder boilirggliquidfrefrigerant 1S JOQCCl-{Hlufhe ,alli Sile?! inpthe evaporator-1i Whenithe temperature-of,thair 9 IeGQYQlT-yzfdeytl110k, deliyere l" throughV the 1* attich'eat recovery "device 107V "i" conduit 107C With an 111 A reaches` a low' value, er g. -25 *F.iand under; and 'a corr-v trolv means '(later' hereindescribed') `is setgvto' sound u an maal@ presa Sure:.=cauge-;.101P, The.: con-.tro meahssalsoftincludes .an- Other-pressure-eaugetSPtcalibrated2in degrees F.. and;i indicative alarm when'V such temperature drop occurs,;th`c equPPQd fwithlhefusulaliadlustabl# high land'iovialal'm' householder Awillfs top pump 17P- end fan 107F,an1 will CollagsilZ-H'apd1231314* Alliqlld fPfessufef'thmlOsa-t startpump`20P; Cold heat transfer -uid Will thereupon L0 lsllcadilnfheeafth@116211.510mg@ area 23,Mar1d bedravvnthrough pipe 16 andcheck valve 20C"by said '15*fopetlYQlY-Fnnncdhbyi'a*conduit 23GWilh'3fndn pump Z012 'and will be forced by thelatter 'through pipes aemf-tmgllel-l-Qll It@ Sadsw gaugelzspf z1jand 22C. to the-beam section'- Qf co'ilsaz whilfgare 'The @19H91 means :iS-meunteda'vnaparel ln-.suitab'lrt buried'in'the earthfheat storage area 123,jthus'kee ping locadxwlthm'lhholle PlOWeI'zS Servdio hQfPaHl-,L th'ehbottomdsectionsofsaidncoils'ZZfQandthe: contiguous 15 (lV-ef cndlltQTS '101: 1 I1dv1025 hlllghf vp0*fiery-switchg lowerilevelsf the. earth'istorage -areaz cooler than 12h-:Conductor lazabemgfthe neutralfnrferounded wire; th'e upper levels of' said area, wherebyto avoid losses of MQumedflonf the-Pane1 'is 'a hfeelpole: :doubler throw: storedheatby dissipation thereon@ thedeep earth undef. switch 103 :anche two, pole, .douhlethrow switch 1 04.'the; lyingmsai@ sitomger'ra 231" The. coldht tr'sfer' id hingefcontaotstof `which are. all;conr1ected top oweriwire Willhe warmedfbyzheat.crammedin.irreemhfhgwy- 5o ma onaterminaroreaanmawrmsr/r;126M,.soM, agg 'area 213 as lSaid flows` upwardlygtlhqugh Succes? 14; 20M; 17M and107Mand amaleir'nl bell 11.7iSzC011r; sively-.higher seetdionsmqfthegoilg 22Lnna11yeys nectedztot-the ground Ywire 102e' Thepowerrswitch.: 2.1; the lati?! hroughpl 22H, l'vfld'lg from' the highest being closed, the householder will close the threerpole, homes? Setin of Saidwcoi'lsl Fromupp 22H the Warm sw-1tch;1ll3;tothe up position `andalso,thestwo poleswitch heatstransfer Huid passesrhthwughr.pipzandpip 1510 55 lrfla-trntrp4 position. 1 Underftheseeconditions; the three end .throughthe coil Vlilof evaporatorf1,and irl,trasvgs pole sswiteh; 163 will aclosecireuitsf,so.that motor 114 will inghsakido 19 gives up itslheat ata rdativeiyfhighjtem drive-..thegheat pump. compressor l3, motorzlMftwillperatureto the boiling refrigerant inevaporator,1`Av In operate pumplrvP: toycirculatefhot, heat-transfer ..uid; this'manner heat s Withdrawn from'the Vearthfstoa-ge throughfthehouse heating device 106, and motorflUML areazlas a Source Gf h'eatfol. Opef'ation ofth heut 60 wrllroperate famlilFrto blow house air; throughgsaid pump heattng-device 106;whilev thettwo .pole switch, will close The; circulation uGf# hat heat'transferuiduisnext Csm circuits sothat-motor 17M will 1operate:.pump;.l7l:?Eto, cir-z sidered, such. circulation is effected by ystopprig,pump `culate coldiheatftransfer fluidthroughtheattio heat:re.- ZOPand starting operation ofrpumpZRwhichis driven www: devl lfandmotor IMM Wi11"'operate ifa bymmol. 26M; Pumpfzphdraws hot het transferuud 65 107B tosb'lowt attic orroutdoor air,;as the..casemaybe,- from Goi nofeondenser? 5 .thmughuc'hek vak/4612.6@ through.,-the. heat;exchanger-1057Ez-offthe 4heat.;recovery. and forces the .-samefthrough'pipe vto andathroughf the dymeilml" when hecontmls am thlls wndltiopedfme houseqheatexchangn 195B: of a house h-ating dvi lfteatfpumgyvvlll bexmstan-dardoperation, reeelvmgihcat 106.1: Fan-136i:- Which. is` driven-by -Inotor1106M Ldrives o lrolllhe'ilcihent hrecvsryldeviceflo; andrdehyemg housefairthroughgsaid heatexchanger 1G6E.andf=thisair l wngsrsNalsl'ailglgtdellol hr is thereby warmed by heat transferredrthretoffromthe SwitcuhzgW-Ai'u be thrown,opsjrsii gag-@ ,ng hot heat transfer riluid andgtheng returned jto theyehouse 31H1-, .L f i .s l space.;l The;cooled.1mm.ftrzmsfernfiuid?. dschargesfmm In bell 117. to the. higlrtemperaturealarmcontact l ZSPI-Lzof. pressure gaugetZSP; so. that operationgof this. the beatfexcharxgerfll.fthroughlplpe128gandfp1peef29 75 =gauge-23P rbythe=earthfheatfstorage area thermostat'-12312v` will ring the alarm bell 117, to warn the householder 'that enought heat is stored in the earth heat storage area. A single pole, double throw switch 119 will be thrown to down position which will condition the pressure gauge 107P for operation by the thermostat 107T associated with the attic heat recovery device 107, whereby to `sound the alarm bell 117 when the temperature of the air circulated through the `attic heat recovery device drops too low to supply enough heat for economical operation of the heat pump, that is when air temperature drops e. g. to 25 F.

If attic or outdoor air serving the attic heat recovery device 107 rises in temperature, e. g. to 50 F., as shown by the pressure gauge 107P, householder will throw control switch 103 yto down position, lthus stopping motor 106M and fan 106F of the house heating device 106, and also stopping motor 26M and pump 26P to interrupt circulation of hot heat transfer fluid through house heating device 106, while at the same time continuing operation of heat pump compressor operating motor 14, and starting mot-or 30M to operate pump 30P, whereby to circulate hot heat transfer fluid through the earth heat storage area coils 22, thus to supply heat to the earth heat storage area 23 for storage therein. This operation is continued until pressure gauge 23P indicates high tempertaure, e. g. 65 F., and closes on high alarm contact 23PH, so that alarm bell signal is given. Under this condition, householder can open switch 103 and stop the heating system, at 'the -sa-me time throwing switch 120 close on low temperature contact 23PL of gauge 23P, so that alarm 117 will sound when temperature of earth hea-t storage area drops to a predetermined low value, e. g. 60 F. If this occurs switch 103 can be thrown down to resume heat storage operation or up to resume house heat dispensing operation.

If 'alarm is sounded to indicate `temperature drop of attic or outdoor air serving the attic heat recovery device 107, the householder will throw switch 104 to down position, whereby to stop operation of motor 107M and fan 107F, and also motor 17M which operates pump 17P for circulating cold heat transfer fluid -through the attic heat recovery device 107, while at the same time starting operation of motor 20M to drive pump 20P, whereby to circulate heat -transfer fluid in such manner as to carry heat from the earth heat storage area 23 to the heat pump evaporator coil 10. Under these circumstances, switch 119 will be thrown up to close on contact 107Ph of gauge 107P, said gauge when reaching its high temperature indicating condition will close the alarm circuit vand ring alarm bell 117, to warn the householder that switch 104 may -then be returned to its normal up position for standard operation of the heat pump and the system.

In Fig. 3 is shown a modified arrangement of the heat pump operated house heating system of this invention.

This modifie-d arrangement differs from that above described and shown in Fig. 2 principally in th-at the refrigerant rather than the heat transfer fluid i-s circulated to and from the hea-t pump through the attic heat recovery device 107 and the house heating device 106, while the heat transfer fluid circulates only to and from the coils 22 of the earth heat storage area 23. In this modified arrangement of the system, the circulation of heat transfer fluid `to conduct heat from the earth heat storage area 23 to the evaporator coil 10 of evaporator 1 is substantially similar to the arrangement in the system shown in Fig. 2, and the circulation of hot heat transfer fluid, whereby to conduct heat to the storage area in average winter weather, and through a condenser coil 12,

is also substantially similar to the larrangement in the b system shown in Fig. 2. However, in this embodiment of Fig. 3, the attic heat recovery device 107 is connected in the liquid refrigerant -circulating line, and whenever the heat pump is operated -to receive heat from the attic hea-t recovery device 107, said device 107 serves as an evaporator, and condensed liquid refrigerant, delivered through pipe 33 is evaporated in the heat exchanger 107B, and the cold refrigerant gas then passes by way of pipe 34 directly through an evaporator 1 to the heat pump compressor 3.

The house heating device 106, in this modified system, is connected directly to heat pump compressor 3 by pipe 4A which leads to the heat exchanger 106B, so that the latter can serve as a condenser for delivered hot refrigerant gas, and thus transfer the heat of condensation to the air blown through the heat exchanger 106B by fan 106F for house space heating effect. The condensed liquid refrigerant discharges from the heat exchanger 106E through pipe 4B, and passes directly to condenser 5, and thence by pipe 35 into a float valve 36 by which its flow to a liquid refrigerant cooler 77 is governed, being discharged from the latter through float valve 78 to pipe 33 through which it passes to the attic heat recovery device 107 for recirculation to the heat pump compressor 3. The liquid refrigerant cooler 77 performs a function similar to that performed by the pipes 7 in the system of Fig. 2, in that sensible heat is given up by refrigerant liquid for transfer by heat transfer fluid to the earth heat storage area 23. In the cooler 77, the liquid refrigerant flows from right to left in counterow relation to cold heat transfer fluid flowing in the cooler contained coil 38 from left to right, said heat transfer fluid being delivered to coil 38 by pipes 22C and 37 from the relatively cool deep section of the coils 22 of the earth heat storage area 23. In so passing through the cooler coil 38, the heat transfer fluid is warmed.

Leaving the cooler coil 38, the warmed heat transfer fluid passes through pipe 39, valve 40 and through a restricted orifice fitting O to pipe 41, and thence to pump 30P which is driven by motor 30M. Pump 30P forces the warm heat transfer fluid by way of pipes 42 and 22H into the hot end of the earth heat storage area coil 22. The restricted orifice fitting O limits the flow of heat transfer fluid through the coil 38 of cooler 77 to a quantity sufficiently small so that the limited amount of condensed liquid refrigerant available in cooler 77 is able to warm the heat transfer fluid to a temperature substantially higher than the temperature of the top level of the earth heat storage area 23. Since the hot liquid Irefrigerant passes through the cooler 77 in counterllow relation to the heat transfer fluid, said refrigerant liquid is cooled nearly to the temperature of the relatively cool bottom level of the earth heat storage area 23.

In normal operation of the modified system of Fig. 3, when temperature of air blown through the attic heat recovery device 107 is e. g. above 25 F., pump 20F is idle, so that refrigerant evaporator 1 serves merely as a conduit to deliver cold refrigerant gas from the attic heat recovery device 107 to the heat pump compressor 3.

In very cold winter weather, if temperature of air serving the attic recovery device 107 drops to e. g. 25 F. or below, the fan 107F of heat exchanger 107B is stopped and said heat exchanger 107B fills up with condensed liquid refrigerant which overflows therefrom through pipe 34 into evaporator 1, while it fills to a normally maintained level 11. Pump 201 is started and operates to draw cold heat transfer fluid from coil 10 in evaporator 1 through check valve 20C, and forces this cold heat transfer fluid through pipe 21 into the deep end of the coils 22 of the earth heat storage area 23, and then-ce upwardly through said coils 22, whereby the heat transfer fluid is warmed by the heat in said storage area 23, and thereupon is returned for recirculation through the coil 10 of evaporator 1. Heat from the warm heat transfer fluid in coil 10 causes the liquid refrigerant in evaporator to boil, and the resultant refrigerant gas to pass to the heat pump compressor 3.

A solenoid coil 84 is connected in parallel with the motor 106M for fan 106F of the house heating device, so that when the fan motor 106 is running said solenoid coil located at upper levels of the tank and cold water at lower levels thereof.

Referring to Figs. 5, 6 and 7, these views show an illustrative structural arrangement of the attic heat reoovery device 107, whereby the air delivered therethrough will be automatically drawn either from indoor attic air or outdoor air, whichever is of higher temperature. The attic heat recovery device 107 comprises a duct structure having an upstanding intake section 1071 at one end, which is open adjacent to the peak of the attic interior, and an upstanding discharge section 107D at its opposite end. Within and across the duct, between the intake and discharge sections, is located the heat exchanger 107B, fan 107F and motor 107M for driving the latter. The discharge section 107D of the duct is provided at its end with an outlet port 98, which opens into the attic interior, and in an adjacent side wall with a second outlet port 97, which opens through a branch duct 107B extending through the house wall W to outdoors. -A damper 86, located within the discharge section 107D of the duct between the ports 98 and 97, is xed on a shaft 87, so as to be movable to selectively close one of said ports and open the other. Temperature responsive means is provided for automatically moving said damper 86 to close either port 98 or port 97 accordingly as outdoor temperature is higher than indoor temperature, and vice versa. This temperature responsive means comprises an indoor Sylphon bellows 96, supported from the interior side of the house wall W by bracket 96A, and an outdoor Sylphon bellows 95 supported from the exterior side of the house wall W by a bracket 95A. These Sylphon bellows contain a volatile substance, such as butane, and the opposed ends of said Sylphon bellows are interconnected by a slide bar 94. Rotatably supported in connection with the attic heat recovery device 107, adjacent to said slide bar 94, is a pulley 89 upon the shaft of which is fixed a forked lever arm 93, the fork of which engages a. laterally projecting co-upler pin 94A aixed to the slide bar 94. To the pulley 89 is anchored a pull cable 92. This pull cable engages around a pulley 88 fixed on a shaft 87 by which damper 86 is actuated. The free end portion 91 of pull cable 92 is attached to an anchored pull spring 90. Pull spring 90 normally exerts pull on cable 92, whereby to rotate the pulley 88 and shaft 87 in direction to swing damper 86 into closed relation to the out-let port 98 which communicates with the attic interior.

In operation, the attic heat recovery device performs as follows: When attic air is at higher temperature than outdoor air, the butane in indoor Sylphon bellows 96 expands and that in outdoor Sylphon bellows 95 contracts.

This results in sliding the slide bar 94 outwardly, to thereby move the forked lever arm 93 to the right, thus rotating the pulleys 89 and 88 counterclockwise, and thereby swinging damper 96 to closed relation to outdoor communicating port 97 and opening port 98. Under these conditions air is taken from the attic interior and passed through the heat exchanger 106B and back into attic. The heat pump is thus served by heat taken from warm attic air.

On the other hand, when out-door air is at a higher temperature than attic air, the butane in outdoor Sylphon bellows 95 expands and that in indoor Sylphon bellows contracts. This results in sliding the slide bai 94 inwardly, to thereby move the forked lever arm 93 to the left, thus rotating the pulleys 89 and 88 clockwise, and thereby swinging damper 86 to closed relation to attic interior communicating port 98 and opening outdoor communicating port 97. Air will now enter the attic space through an intake passage means 153 (see Fig. l), and will be passed through the heat exchanger 107E and thence back outdoors through port 97 and branch duct 107B. The heat pump is thus served by heat taken from outside air.

In the operation .of the illustrative embodiments of the heat pump operated house heating system according to this invention, when spring weather arrives, and prolonged cold weather spells are not likely to occur, charging of heat into the earth heat storage area 23 may be discontinued, and heat may be extracted from the earth heat storage area 23 whenever the temperature of said area is higher than that of outdoor air passed through the attic heat exchanger 107B.

In systems according to this invention in illustrative embodiments such as shown in Figs. 2 and 3, wherein an earth heat storage area 23 has imbedded therein heat tnansfer coils 22, it is desirable to provide in connection with said coils 22, between the same and the underlying earth mass, a thermal check valve structure which functions to transmit heat from deep earth to the coils 22 and the earth heat storage area 23 surrounding the latter, but which operates to prevent dissipation of heat to deep earth from said coils 22 and the surrounding earth heat storage area 23. One practical form of such thermal check valve structure is shown in Figs. 8 to 10 inclusive, and includes a series of one way heat conductive devices 70. Each said device comprises a hollow, substantially flat thin metal envelope, preferably of the perpendicularly ribbed formation shown in Fig. 10 whereby to strengthen and reenforce the same against collapse or distortion. Each said envelope is filled to a level 75, spaced a substantial distance below its upper end, with a low boiling point liquid, such as butane. These oneway heat conductive devices extend between adjacent courses of the coils 22, i. e. from a lower course to a next course above, and are fastened thereto by thermally conductive concrete 72 composed of cement containing, as aggregate, a highly heat conducted material such as iron filings, steel chips or the like. To the lowest courses of the coils 22 are fastened a type of one-way heat conductive devices 71 which can be driven into the deep earth underlying the earth heat Storage area 23. These latter devices are preferably in the form of metallic tubular members, closed at their upper ends by caps 77, and at their bottom ends by sharpened driving members 76. Each tubular member is filled to a level 78, spaced a substantial distance below its closed upper end, with a low boiling point liquid, such as butane. Each device is driven downward into the earth underlying the earth heat storage area 23, whereupon its upper end is fastened to a lowest level course of coils 22, by a thermally conductive concrete 72 such as already above described.

The thermal check valve structure functions as follows: Heat from deep earth contacting the tubular members 71 will cause the liquid contained therein to boil, and the resultant vapor at the cooler top of said members will condense, so that the heat of condensation will be transferred to the low courses of the coils 22. Heat from the low courses of the coils 22 will cause the liquid contained in the envelopes 70 to boil, and the resultant vapor will be condensed, so that the heat of condensation will be transferred to the earth of the earth heat storage area. In this manner heat may be recovered from deep earth in very cold winter weather. Since flow of heat downwardly through the thermal check valve structure cannot take place, said structures inhibit escape of any substantial amount of heat from the coils 22 and the surrounding earth heat storage area 23 to deep underlying earth.

In the system embodiment of Fig. 4, use of the thermal check valve envelopes 70 between courses of the coils 22 submerged in the water of the tank 55 is not necessary, and the thermal check valve structure may be 1imited to the inclusion of the tubular members 71 arranged to extend between bottommost courses of the coils 22, through the tank bottom, 'into deep earth, so that heat conducted from the deep earth is transferred substantially directly to the water content of tank 55.

The eciency of the heat pump operated house heating system of this invention will be enhanced, when used ina house `structure a substantial part of the living space v I3 thereof extends"belo`w ground;` surfaeefleveland iirtoi'the earth' adjacent the earth` heat: storage area; smc ing space contlig'uijnis-.` to the earth`will' be'maintarii dryiandlivablecondition g The operationl andadvantages'of thefhtpumii operated house heat-'ingfsystenrof this invention"fisindicatd by the gnaphsof'Figs. 1 l, 12 and 13..

In Fig. 11, th'ecurve G indicates B; t. u; perihonr plotted vertically: against outdoor. teniperatlire fplot""d hol''zortally, and' represents Va hieaf purp having "Sfiet capacity to heat a houserequirirgainet heat input of 67,500 B. t. u'.O per liourat zeroE outdoorv temperature; saidhousebeingeected'abovegrundlevellv V Curve F represents theoutputniriB. t. ufpfehor, plotted" as ordin'at'eagist' outdoor"temperatuideg. Pfasabsciss, Areflui'red to heat a hous'e'ofth'e sainev size as Ain curve G fbut 'partially buried'in Athe 'earth and having the attic builtiinf'thr `forrri`of a Solar heat'trapf'and having the earthundr th house heated."V l l CurveE Vrepresents la heat pump` able `to'fsifxp'ply 36,000 Bi t. u. per hour atwzeio deg. and?" b le tofsupplyf'the 41,00`"B. t. u. p'erV hour requiredib' andf able te supply aufiie; reggirememspf'gthe Uh uses taking heat from the earth at alterriperature of. deg. Since Vit isfpropsd' in'.'thiswtesign toluintirfuil eartlitemperature seldom" less than 60`F."` A willbe ablehto supplyuthe heatrequi' house. However, in orderftofhaye. a "su y v factor even. after` an unusually loii'g'col-d 'spellfthehe't pump, having an output in `accc'xrdanc'e ,withx..curv`e'"B might be used; i. e., having exactly one-halfthe capacity of heatpump (curveG). 4 p

InA Fig. 12 curvey A represents an approXimatedur'atiorrcurveY of outdoor temperature' deg. F. againsthours peryear in the" metropolitan district aroundvNew York.

Curve B is obtainedfrom. cur'vc` A by plotting-,directly under. any' temperature on curve A .the vheat..i'c'equirement of the house as shown on curveN, Fig. 1l, lfortlrat temperature; it therefore gives the B. Yt.u..per4 hour plotted at the extreme right against hours duration' as abscissa f l i Y ,i I

The cur've .Clele'ctrical input in B." T, U. per-hour as ordinate .against hours duration as absissawis obtained by :dividing the "requirements as shown' on curve B 'by the coei'cieht'of performance at that teinperatu'reA as onfpagre'y555 of the luly 195 1' magazine of Mec al Engineering. These' coeiricienfr are' plotted arabe-'levier gefangene Vdemand as ordinate on the extreme left anddrfrat'infin the coefficient "of 'performancewillihef instead 0132.5 'and thfmaxirnunwdeinad will'be-'redued'm ene-y alf by.A reason ofthe fact thatithefheatgpumpfi's receiving heat from thefiearth atf60` F. atacoetientfof performance of '5,'i whilethefheatptmrp 'FG (Fig: 11 received heat' 4from outddor'lairv at zero'F; at a'ic'oeiciet of performance' of tainediri thef forcgoingdescription "or 'shown in' the accompanying drawings shall be interpreted' as illiistrative andnot in aliiniting sense'.`

I claim:

l. Ina house heatingffs'ystem employing' a 'heat pump, an earth Vheat storage :area unde'r the hous'to receive andstore heatfron said pump inl the' warmest winter weather whenthewhouse'spacedoes not require heat and to serveas` a'irelatively highl temperature heat lsource for z'sai'd pump'irrthe coldestwi'nter weather'whe'n the' house space needs heat,1 conduit means l:between the--heatpunip and storage'areafor conducting Y:heat transfer liuid `from one..to.the"other; said conduit meansi'ncluding'coils'im- .bedded inthe earth ofsaid'stora'ge areaisaidcoils' having 'courses' thereof Iperpendicularly spa-ced `within said earth,

saidxconduit' means beingvso connectedfwith the heat pump that warm: heat transfer` fluid' moving-from the pumpv to. the storage Yareaenters the high level courses ofthe conduit coilsiand back to the. pump from the low level-.courses of said conduit coils but when .heat transfer uidgiscirculated. to supply .heat to the pump the same is drawn from the high level curseseof'the conduit coils andreturned to the lowlevel courses thereof, and'oneway thermally conductive' devices connected between low level and high level courses of -said conduit coils operativel to induce upward iliwvgof heat therehetween, said devices operating toltransfer heat to the storage arca earthduring delivery ofthe heatyoutput ofl the heat pump .thereto, .said devices beingjadapted,l on the other hand,

to receive heat from the.l storage-area earth and-conduct it tok heattransfer fluid circulated in Said conduit coils when supplyingheat from storagefto the heat pump, whereby dissipation of stored-fheatto deepearth under- Hlying the storage area isvreduced'to a minimum.

storage area.

3. In a house heating system, an electrically operated vheat pump including an evaporator and a condenser, heat transfer uid upon which the heat pump operates, a heat vstorage means provided by the earth beneath the house to be heated and comprising an upper level storage earth 'area and an underlying lower level storage earth area,

heat transfer fluid conducting means comprising an upper `section extending through the upper storage earth area 'and a lower section extending therefrom through the lower storage earth area, means operable during a heat vstorage period adapted to circulate hot transfer uid through said conducting means in one direction, a sec- -ond means operable during a stored heat withdrawal period to circulate cool transfer fluid through said conducting means in the opposite direction, said first mentioned circulating means comprising a means operative to move hot transfer fluid from the heat pump condenser first through the upper section of said conducting means which contacts the upper storage earth area, then on through the lower section of said conducting means which contacts the lower storage earth area and thence back to said condenser, and said second mentioned circulating means comprising means operative to circulate cool transfer uid from the heat pump evaporator first through the lower section of said conducting means which contacts the lower storage earth area, then on through the upper section of said conducting means which contacts the upper storage earth area and thence back to said evaporator, all whereby said upper storage earth area is maintained at a relatively high temperature and said lower storage earth area is maintained at a relatively low temperature so that heat loss to deep earth is held to a minimum.

4. In a house heating system according to claim 3, one-way thermal check valve means cooperative with said conducting means and operative to transmitheat from underlying deep earth to the storage earth areas and to the sections of said conducting means extending through the latter, whereby dissipation of heat from the storage earth areas to deep earth is counteracted.

5. A house and heating system therefor including an electrically driven heat pump having an evaporator and a condenser normally operative to pump heat from outdoor air to heat the house space, said house including an attic space having a roof constructed to pass solar energy therethrough to raise the temperature of 4attic air during sunny winter days, an external cover for said roof adapted to insulate it from cold winter air without impeding transmission of solar energy, an attic heat recovery device connected by heat transfer uid conduit means with the heat pump evaporator whereby to supply heat from the attic air to said evaporator, damper means operative to control movement of either attic air or outdoor air through the attic heat recovery device whichever is warmer, means responsive to both attic and outdoor air temperature for actuating said damper, a house space heating device connected by heat transfer uid conduit means with the heat pump condenser to receive heat from said condenser, a heat storage area provided by the earth adjacently underlying the house space, heat transfer fluid conducting means imbedded in the storage earth area, means to circulate hot transfer uid from the heat pump condenser through said conducting means, whereby to transfer heat to said storage earth area when heat is not required by the house space heating device, and means to circulate cool heat transfer fluid from the heat pump evaporator through said conducting means, whereby to transfer heat from said storage earth area to the transfer fluid and said heat pump evaporator during extreme cold weather.

6. A house and heating system therefor including an electrically driven heat pump having an evaporator and a condenser normally operative to pump heat from outdoor air to heat the house space, Isaid house including an attic space having a roof constructed to pass solar energy therethrough to raise the temperature of attic air during sunny winter days, an external cover for said roof adapted to insulate it from cold winter air without impeding transmission of solar energy, an attic heat recovery device connected by heat transfer lluid conduit means with the heat pump evaporator whereby to supply heat from the attic air to Isaid evaporator, damper means operative to control movement of either attic air or outdoor air through the attic heat recovery device whichever is warmer, means responsive to both attic and outdoor air temperature for actuating said damper, a house space heating device connected by heat transfer fluid conduit means with the heat pump condenser to receive heat from said condenser, `a heat storage means provided by the earth beneath the house and comprising an upper level storage earth area and an underlying lower level storage earth area, heat transfer lluid conducting means comprising an upper section extending through the upper storage earth area and a lower section extending therefrom through the lower storage earth area, means operable during a heat storage period to circulate hot transfer fluid through said conducting means in one direction, a second means operable during a stored heat withdrawal period to circulate cool transfer uid through lsaid conducting means in the opposite direction, said first mentioned circulating means comprising a means operative to move hot transfer fluid from the heat pump condenser first through the upper section of said conducting means which contacts the upper storage earth area, then on through the lower section of said conducting means which contacts the lower storage ,earth area and thence back to the condenser, and said 'second circulating means comprising means operative to circulate cool transfer fluid from the heat pump evapo` claim 6, including one-way thermal check valve means cooperative with the earth imbedded heat transfer fluid conducting means to transmit heat from underlying deep earth to the storage earth areas and to the sections of said conducting means extending through the latter, whereby dis- 'sipation of heat from the storage earth areas to deep earth is counteracted.

8. In a house heating system, an electrically driven 4heat pump comprising a refrigerant evaporator, a refrigerant compressor and a refrigerant condenser, a heat storage area in earth beneath the house, heat transfer fluid conducting means extending through said heat storage area, a heat transfer fluid conductive coil within the heat pump evaporator and connected in circuit with said heat transfer fluid conducting means traversing the heat storage area, another heat transfer fluid conductive coil within the heat -pump condenser also connected in circuit with said heat transfer fluid conducting means traversing the heat storage area, the house containing an attic space, a metal roof over said attic space, a cover for said metal roof adapted to insulate it from cold blasts of winter air yet allowing solar energy to pass freely therethrough, whereby `the attic air is heated during sunny winter days, an vattic Vheat recovery device, means for circulating heat transfer fluid from the evaporator coil through `said attic heat recovery device, whereby to supply heat from attic air to the heat pump, alternate means for circulating heat transfer lud from the heat transfer tluid conducting means of the storage area through said evaporator coil, whereby to supply heat from theheat storage area to the heat pump, a house heating device, means for circulating heat transfer uid from the condenser coil through -said house heating device, whereby to supply heat to the house space, alternative means for circulating heat transfer huid from said condenser coil through the heat transfer fluid conducting means traversing the heat `storage are-a, whereby to charge heat into said storage area, anda damper means operative in the attic heat recovery device to control movement therethrough of either attic or outdoor air, whichever is warmest, and means responsive to attic and outdoor air temperatures operative to automatically actuate said damper means;

References Cited in the le of this patent UNITED STATES PATENTS French Apr. 26, 1915 Otis Aug. 24, 1943 Hawkins Oct. 14, 1947 Clancy June 28, 1949 StelzerV Oct. 11, 1949 Sporn July 4, 1950 Gay Feb. 5, 1952 Levine May 27, 1952 Wetherbee Sept. 14, 1954 Marchant Nov. 9, 1954 

